System 1m, using ADSR with other eurorack modules

[mandala]

Hello, I'm trying to integrate my System 1m with other Eurorack modules I've got.
While I can send System 1m LFO to modulate something external, if I use filter or amp envelopes nothing happens. How do these envelopes work exactly?
I've tried triggering the system 1m amp envelope, sending a gate signal from external sequencer into "ENV in" and then using "ENV out" to go to "VCA in" of my external vca module, but no signal arrive into module.

Any help? Manual doesn't cover these aspects unfortunately.